Stray light barrier structure of reflection measuring apparatus

摘要

A reflection measuring apparatus such as a laser radar is provided which emits a laser beam using a scanner and receives a return of the laser beam from an object present in a scan range to obtain positional information about the object. The apparatus includes a stray light blocking plate which has a beam exit opening formed on an optical path along which the laser beam travels from a light source to the scanner. The stray light blocking plate has a barrier wall defined around the beam exit opening which works to interrupt traveling of the stray light produced optically upstream of the beam exist opening to the scanner. The barrier wall has a surface which tapers off in cross section thereof to the beam exist opening, thereby minimizing reflections of the stray light on an inner surface of the barrier wall defining the beam exit opening to the scanner.